Tag Archives: larvae

I was out at Manchester yesterday to help Laura out with getting things going.

tldr- Water is flowing, rising temperature seems to be an issue. This could be attributed to air temp and/or pumps.

When we arrived water temperature was up to 19C after about a week. We decided to drain down system refill, calibrate Durafets, and monitor system over next few days with respect to temperature and pH.

Here is the system draining..
[youtube https://www.youtube.com/watch?v=CtDfMPkK69E?rel=0&showinfo=0]

As the system drained we calibrated with NBS buffers (7-4-10). In actuality I think they were only calibrated at 7 and 4. Need to confirm calibration system with Honeywells.

Probes are designated pink, blue, green, and yellow. Two in treatment tanks and two in each of experimental systems. As we placed in 7 buffer they initially read as follows

pink – 6.6

blue – 6.98

green – 6.82

yellow – 6.89

After all were calibrated we went through buffers and just read.

Here are more #s

Tour time (if you listen closely you can hear a narration)
[youtube https://www.youtube.com/watch?v=K5xkpAAVSuI?rel=0&showinfo=0]

As the system started to refill with ambient water (10c) this is how the pH probes read.

This is without any C02 input. We then “sample calibrated” experimental system to read same pH

At the end of the day pH was set to 7.5 in treatment tank and we will monitor to see how temperature and pH holds (assuming it can adjust with high flow rates). For more on this day check out Laura’s post.

I will leave you with an inside look at treatment tanks. Note that the first tank in the video (Tank #2) has less water coming in from the head tank as compared to Tank #1.

To be sure files are accurate, I will intersectbed again. Based on recollection there is likely not a difference in proportion based on all TEs. This brings up a an important point of how to record “negative” data that does not go into a paper.

Continued helping on Dan’s Pacific oyster familial crosses project at the Puget Sound Restoration Fund (PSRF) hatchery at Manchester Research Station in Manchester, WA. Pacific oyster (Crassostrea gigas) families were crossed based on earlier genotyping. Here’re some pics of the day:

Today Sam and I took care of the daily maintenance of F2 Olympia oysters grown at the Ken Chew Shellfish Hatchery at Manchester, WA. In short, larvae are being described from Fidalgo (North: NF), Oyster Bay (South: SS), and Hood Canal (HC) broodstock. Though I had done most aspects before, never without Katherine, thus she provided instructions.

When I arrived the algae tank was empty and pump was off.
The system was flushed with freshwater (with Sam soaked with said water) along with bleach. The algae tank was filled. The first set of tanks that were processed were the larger larvae (+160um).
Using 100um screen larvae were collected, brought up in 800ml and 0.5ml (x3) taken for counts.
The remaining larvae were placed back into cleaned systems.

Next, the smaller larvae tanks were processed, using 160 over 100 um screens, with larger ones moving over to +160um tanks (above). For this counts were done for both size classes and DNA samples taken for 160 size class. The smaller larvae placed back in the same tanks.
For DNA samples, 4mls of larvae from 800ml beaker were taken, rinsed with ethanol and placed in 1.5ml centrifuge tube with 1ml of RNAlater (This was also done with fresh larvae- below).

The last systems tackled were the “new”, fresh larvae from collectors..
For this, larvae were captured using 200um / 100um screen, with larvae moved to larger tanks, counts done, and samples collected for DNA. As expected very little larvae, they were brought up in 400ml, 1ml used for counting, and 8ml used for DNA samples.

For purposes of proposaling and reports, I have gone back to look at a small project done in collaboration with scientist at IFREMER looking at pesticide exposure on oyster larvae methylation.

The control library had limited yield so the number of loci with data from the treated and the control library was restricted. However using a liberal 3x coverage for both, we found a total of 823 DMRs (544 hypermethylated and 279 hypomethylated).

Intriguingly, when one accounts for all CGs in the genome, these DMRs are predominantly in transposable elements.